Gun Nuts Pro Line - Fire Control Group. Specifications for Gun Nuts Pro Line Fire Control Group: Manufacturer: Gun Nuts Trigger Shape: Curved Trigger Material: 8620 Steel Trigger Pull Weight: 5.5 lb Trigger Pin Size: 0.154 in Gun Make: AR Platform Condition: New Finish: Phosphate Features of Gun Nuts Pro Line Fire Control Group Entry Level Cost Effective Mil Equivalent Single Stage for builders and SHTF Kits. Package Contents: Gun Nuts Pro Line Fire Control Group Gun Nuts SI-FCG-PRO: Pro Line - Fire Control Group